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Nano-Crystalline Alloy VITROPERM

 

Nano-Crystalline: what does it mean ?

The characteristic feature of nano-crystalline materials is a two-phase structure in which a fine-crystalline grain with an average diameter of 10 to 20 nm is embedded in an amorphous residual phase. This structure is responsible for the fact that these materials can reach the highest permeabilities and the lowest coercivities. In addition, their small strip thickness (approx. 20µm) and relatively high electrical resistivity result in extremely low eddy-current losses and excellent frequency behaviour and permeability. Together with a saturation flux density of 1.2 Tesla and favourable thermal properties, these characteristics make VITROPERM equal or even superior to permalloys, ferrites or amorphous cobalt based alloys.


Cost-effectivity:
  • Production of ribbons in one step directly from melt (rapid solidification)

Special properties:
    match peak values - permeability coercivity and core losses - of the amorphous Co-based
    alloys or thin strip crystalline 80 % NiFe alloys and are superior in:
  • saturation flux densitiy (abt. 50-100 % higher)
  • temperature stability (up to abt. 150°C permanent temperature)
  • less expensive alloy components

Typical properties
  • The nano-crystalline condition is created by a heat treatment at temperatures >500°C out of a material condition which is originally amorphous. After this heat treatment the material is extremely briddle; thus, only the end product can be heat-treated, as a rule this is a toroidal core. By using magnetic fields during heat treatment defined shapes of hysteresis loops can be created.

Forms of supply:
  • Semi-finished material exclusively in form of thin metal foils (strip thickness approx. 23 mm and a maximum strip width of (presently) 25 mm
  • or preferably: Toroidal strip-wound cores and
    Inductive Components /ZKB